Graphics teaching machine

ABSTRACT

A graphics teaching machine for teaching a student includes: a graphic answer input device, a logic unit and a data unit interconnected in series, as well as a control unit connected to the logic and data units. The logic unit in turn comprises a coder, a decoder and a comparison assembly interconnected in series, while the data unit comprises a &#39;&#39;&#39;&#39;prompting&#39;&#39;&#39;&#39; assembly, a display and a mark-giving assembly interconnected in series, the input of each of these assemblies being connected to the output of the comparison assembly. The decoder uses an AND-circuit that operates in case the student gives a correct answer, and a delay element resetting this circuit to its original state with certain time delays after its operation.

United States Patent [1 1 Tarnopolsky et al.

[ GRAPHICS TEACHING MACHINE [76] Inventors: Igor RafailovichTarnopolsky, ulitsa Zavooskaya 33, kv. 27; Gennady Vasilievich Akimtsev,ulitsa Furmanova 23, both of Frunze,

U.S.S.R.

Primary Examiner-Wm. H. Grieb Attorney-John C. Holman, Herbert Cantor,Marvin R. Stern and Dennis O. Kraft (4 1 May 1, 1973 ABSTRACT A graphicsteaching machine for teaching a student includes: a graphic answer inputdevice, a logic unit and a data unit interconnected in series, as wellas a control unit connected to the logic and data units. The logic unitin turn comprises a coder, a decoder anda comparison assemblyinterconnected in series, while the data unit comprises a promptingassembly, a display and a mark-giving assembly interconnected in series,the input of each of these assemblies being connected to the output ofthe comparison assembly. The decoder uses an AND-circuit that operatesin case the student gives a correct answer, and a delay elementresetting this circuit to its original state with certain time delaysafter its operation.

4 Claims, 2 Drawing Figures r- -'1 GEfiPH/C I AA/SWE/Q co az Zia-c005 1M/ ur l l 7 I 1*; I /7 M 22% Pan/0 C35??? 2 I I COAZZZi/sa/V I L 1 if Fl 1 l i PPOMPT/A/G 486171148 i i vlspmr 1 i I I I/ i l L LVD [V5 I L JMme/c 671 0116 0 4 7 u/v/r GRAPHICS TEACHING MACHINE BACKGROUND OF THEINVENTION Field of the Invention The invention relates to teachingmachines and, more particularly, to machines for graphics teaching.

The present machine is intended for teaching and checking the knowledgeof students in descriptive geometry and technical draftsmanship. It canalso be used in studying other technical physical and mathematicalbranches of science where graphical solutions of problems are possible.

Widely known in the art are graphics teaching machines that comprise: astudents graphic answer input device, a logic unit, a data unit and acontrol unit. The students graphic answer input device in such machinescomprises the following elements superposed on one another: acontact-bearing board, a punched card, a current-carrying plate and aproblem blank. The logic unit coupled with the answer input device ismade up of a coder, a decoder and a comparison assembly, all connectedin-series, while the data unit contains a prompting assembly, a displayand a markgiving assembly, also connected in-series. Coupled with thedata unit and the logic unit is a control unit.

The above machine operates as follows.

The student using drawing instruments plots a line or figure on theproblem blank of the answer input unit and then punctures the problemblank at certain points of the drawn line with the help of a pair ofconducting compasses. If the plotting of the drawn line has been donecorrectly and the contact points (punctures) have been marked properly,two contacts of the contactbearing board will close and produce anelectric pulse that will be fed to the logic unit of the machine. Herethis pulse will be compared against the programme stored in the memoryof the machine.

After the answer is compared against the stored programme, it is eitheraccepted or rejected by the machine. The result of the comparison ismade known to the student by a display providing a corresponding audioor light signal. In case a first part of the problem is solved correctlythe machine will be ready to receive the answer to the subsequent partof the problem. If the answer is wrong the student will have to continuesolving the incorrectly solved or unsolved part of the problem until hecan feed the machine with a correct answer.

However, the above said machines known in the art suffer from a numberof serious disadvantages.

Firstly, although such machines require that the student gives hisanswer in the graphical form, they, nevertheless, require that he shouldadditionally spend some time and efiort to carry out the contactingprocedure.

Secondly, the result of making contacts of the contact-bearing boardwith the compasses is ambiguous since any straight line contains aninfinity of point pairs defining this line. Therefore, to enable thestudent to select two definite points on a line of the plot he isdrawing, it is necessary either to specify or precondition the selectionof the contacting points. And this is practically unattainable, thewhole idea of plotting the required drawing in this case becomes futile.ln fact,,if the student is given the positions of contacting pointsbeforehand, there will be no need for him to plot the required lineaccording to other parameters he might choose.

SUMMARY OF THE INVENTION The object of the present invention is toprovide a graphics teaching machine which will allow a student topresent his graphical answer in the natural way, i.e. by actuallyplotting the lines of a drawing, diagram or chart without performing anyauxiliary actions or operations.

This object is achieved by providing a graphics teaching machinecomprising: a students graphic answer input device having acontact-bearing board, a punched card, a current-carrying plate and aproblem blank, all successively superposed on one another; a logic unitcoupled with the answer input device and incorporating a coder, adecoder and a comparison unit, all connected in series; a data unit madeup of a prompting assembly, a display and a mark-giving assembly,connected in series, an input of each of said assemblies being connectedto an output of the comparison assembly; a control unit connected to thedata unit and to the comparison assembly, in which, according to theinvention, the decoder comprises an AND- circuit operating when thestudents answer is correct and having its inputs connected to the answerinput device via respective identically connected diodes of the coder,and a delay element resetting the AND circuit to its original state witha given time delay after its operation, the input of the delay elementbeing connected to the output of the AND-circuit.

The herein disclosed graphics teaching machine ensures the natural wayof students work, requires no special training of the user and is highlyreliable. Besides, it provides for quick automatic changeover from oneprogramme to another to be performed by the student himself.

BRIEF DESCRIPTION OF THE DRAWING The invention will be better understoodfrom the description of an embodiment given by way of example withreference to the accompanying drawings, in which:

FIG. 1 is a block diagram of a graphics teaching machine;

FIG. 2 is a schematic diagram of the decoder of the machine logic unit,according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT The graphics teachingmachine disclosed herein comprises a grphic answer input device 1(FIG. 1) containing a contact-bearing board, a punched card, a current-carrying metal resilient plate and a problem blank, all superposedsuccessively on one another (not shown in the drawing). This device I iselectrically coupled with a coder II a, a decoder II b and a comparisonunit or assembly II c which are connected in-series to form a logic unitll of the machine. The logic unit, in its turn, is coupled with acontrol unit III of the machine and a data unit IV which is alsoelectrically connected to the control unit III. The data unit IV is aseries combination of a prompting assembly IV a, a display lV b and amark-giving assembly IV 0.

The decoder (FIG.2) is arranged as an AND-circuit the inputs 1, 2, 3 and4 of which are connected to the graphic answer input device 1 (FlG.l)via respective identically connected diodes 5, 6, 7 and 8 of the coder11 a. The output of the AND-circuit is connected to the comparisonassembly [I via a delay element 9 and an electromechanical relay 10.

The AND-circuit can be arranged, for instance, around fourelectromechanical relays l 1, 12, 13 and 14 with corresponding groups ofcontacts 11, 11" and 11'', 12', 12", and 12'', 13, 13" and 13", 14, 14"and 14'.

The machine is provided also with a control unit lII intended to connectit to a power supply (not shown in the drawing) as well as to select themachine mode of operation (Check-Teach).

The machine operates in the following way.

While plotting the required element of the drawing on the problem blankof the graphic answer input device 1, the student by pressing his pencilagainst the paper makes the current-carrying resilient metal plate(foil) sink through holes in the punched card, due to which the foiltouches the group of contacts on the contact-bearing board located alongthe line drawn by the student.

If the student has drawn the line in accordance with the presetmemorized programme the foil sinking through the holes will touch alsothe two contacts of the contact-bearing board that define the requiredstraight line. Simultaneously each of the two contacts will feed thelogic unit ll (FIG. 1) of the machine with two separate signals each ofwhich will also be applied to the coder Ila. Now, if these signalscorrespond to the preset programme, they will pass through therespective inputs 1, 2, 3 and 4 (FIG.2) to the decoder llb. Here, thesignals passing through the conductors 2 and 3 arriving at relays 1 1and 12 will block the latter, while the signals through the conductors land 4 will block relays 13 and 14. Since the relays ll, 12, 13 and 14are blocked, a signal will arrive at the comparison assembly llc to benoted as a correct solution of the instant part of the plotting made bythe student. Besides, the comparison assembly lIc delivers a signal tothe display lV b of the data unit 1V to inform the student that hisanswer has been accepted (one of the indication lamps of the display lVb goes out). After the student finishes plotting all the pre-programmedlines of the required drawing and does this correctly, the machine willalso trigger a light indicator Problem solved (not shown in the drawing)and the mark-giving assembly IV 0 which (in the Check" mode) will showto the student the mark he got that appears on a digit tube (not shownin the drawing either).

To enable the student to present any number of answers to the problemspre-programmed in the machine, the circuit of the latter is arranged sothat when the relays 11, l2, l3, and 14 operate their contacts 11", 12",13" and 14" will also be blocked. This will enable the delay element 9to function for a period required for the operation of the successiverelays of the comparison assembly llc. After said period of functioningof the delay element 9 and after the preset time period for the signalsto arrive from the decoder Ilb to the comparison assembly He is over,the delay element 9 will, disconnect the output by means of the relayl0, whereupon the supply circuit of the relays 11, 12, 13

and 14 which thus will become unblocked.

Now these relays are again ready to receive a new group of signalscorresponding to the next step of the plotting.

In case the student finds it difficult to solve a part of the problem hecan apply for help to the machine which will prompt him after he pressesthe respective button. The prompt is presented in the form of an imageon a transparent screen. Every prompt is a film frame with the graphicimage of a part of the plot to be drawn according to the problem.

In he Check" mode, the mark-giving assembly lVc notes every case whenthe student asks the machine to prompt him. Moreover, these cases arenot only noted but are also differentiated as regards the complexity ofthe problem. After the student finishes solving the problem the machinepresents a result in the form of a mark 2, 3, 4, or 5.

What is claimed is:

1. A graphics teaching machine comprising: a students graphic answerinput device with a contact-bearing board, a punched card to besuperposed on said contact-bearing board, a current-carrying conductivesheet superposed on said punched card, a problem blank which is used bythe student to write upon and which is superposed on saidcurrent-carrying conductive sheet which electrically contacts thecontact-bearing board through apertures in the punched card when thestudent draws on said problem blank; a logic unit coupled with saidgraphic answer input device and incorporating a coder employing diodes,a decoder connected to said coder and including an AND-circuit having aplurality of inputs and an output and operating when the student gives acorrect answer and which is connected to said graphic answer inputdevice via said diodes connected identically at said inputs of saidAND-circuit, a delay element which resets said AND- circuit to itsoriginal state with a given time delay after its operation and which isconnected to this AND-circuit, a comparison assembly connected to saiddecoder and having an input and an output; a data unit coupled with saidlogic unit and including a prompting assembly having its input; adisplay connected to said prompting assembly, a mark-giving assemblyconnected to said display and having its input, the input of each ofsaid, prompting assembly, display and markgiving assembly beingconnected to the output of said comparison assembly; and a control unitconnected to said data unit and to said logic unit, effecting powersupply to the teaching machine.

2. A graphic teaching machine as claimed in claim 1,

wherein said AND-gate has four inputs, each of said four inputs beingconnected with a corresponding diode of said coder.

3. A graphic teaching machine as claimed in claim 1, wherein the outputof the AND-circuit is connected to said comparison assembly via saiddelay element and an electromechanical relay whereby the AND-circuit maybe reset to its original state.

4. A graphics teaching machine as claimed-in claim 1 wherein saidconductive sheet is a resilient metal foil.

1. A graphics teaching machine comprising: a student''s graphic answerinput device with a contact-bearing board, a punched card to besuperposed on said contact-bearing board, a currentcarrying conductivesheet superposed on said punched card, a problem blank which is used bythe student to write upon and which is superposed on saidcurrent-carrying conductive sheet which electrically contacts thecontact-bearing board through apertures in the punched card when thestudent draws on said problem blank; a logic unit coupled with saidgraphic answer input device and incorporating a coder employing diodes,a decoder connected to said coder and including an AND-circuit having aplurality of inputs and an output and operating when the student gives acorrect answer and which is connected to said graphic answer inputdevice via said diodes connected identically at said inputs of saidAND-circuit, a delay element which resets said AND-circuit to itsoriginal state with a given time delay after its operation and which isconnected to this AND-circuit, a comparison assembly connected to saiddecoder and having an input and an output; a data unit coupled with saidlogic unit and including a ''''prompting'''' assembly having its input;a display connected to said ''''prompting'''' assembly, a mark-givingassembly connected to said display and having its input, the input ofeach of said, prompting assembly, display and mark-giving assembly beingconnected to the output of said comparison assembly; and a control unitconnected to said data unit and to said logic unit, effecting powersupply to the teaching machine.
 2. A graphic teaching machine as claimedin claim 1, wherein said AND-gate has four inputs, each of said fourinputs being connected with a corresponding diode of said coder.
 3. Agraphic teaching machine as claimed in claim 1, wherein the output ofthe AND-circuit is connected to said comparison assembly via said delayelement and an electromechanical relay whereby the AND-circuit may bereset to its original state.
 4. A graphics teaching machine as claimedin claim 1 wherein said conductive sheet is a resilient metal foil.